Re: [PATCH 2/4] firmware: arm_ffa: Register core as a platform driver

[Nathan Chancellor <nathan@kernel.org>]

Hi Sudeep,

On Fri, May 08, 2026 at 06:54:16PM +0100, Sudeep Holla wrote:
> Move the FF-A core bring-up and teardown paths into platform driver
> probe and remove callbacks, and register a synthetic arm-ffa platform
> device to bind the driver.
> 
> This makes the FF-A core lifetime follow the driver model while keeping
> the device creation internal to the FF-A core. Use normal platform driver
> registration so the probe path has standard driver-core semantics.
> 
> The synthetic platform device is a temporary bridge until ACPI and
> devicetree describe the FF-A core device or object. Once those firmware
> description paths are defined, the internal platform device creation can
> be dropped and the driver can bind to the firmware-described device
> directly.
> 
> Since the transport selection now happens from the platform probe path,
> drop the __init annotation from ffa_transport_init().
> 
> Signed-off-by: Sudeep Holla <sudeep.holla@kernel.org>

I am seeing

  arm-ffa arm-ffa: probe with driver arm-ffa failed with error -95

on my two arm64 test machines after this change landed in -next as
commit e659fc8e537c ("firmware: arm_ffa: Register core as a platform
driver"), is this expected? If so, perhaps it should be silenced?

Cheers,
Nathan

# bad: [c1ecb239fa3456529a32255359fc78b69eb9d847] Add linux-next specific files for 20260522
# good: [6779b50faa562e6cca1aa6a4649a4d764c6c7e28] Merge tag 'pci-v7.1-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
git bisect start 'c1ecb239fa3456529a32255359fc78b69eb9d847' '6779b50faa562e6cca1aa6a4649a4d764c6c7e28'
# bad: [c09bb0d7c56d56daed51e374409472c3fece9931] Merge branch 'for-next' of https://git.kernel.org/pub/scm/linux/kernel/git/ath/ath.git
git bisect bad c09bb0d7c56d56daed51e374409472c3fece9931
# bad: [42b0664d6f7b3d04f961e0709811280e52d4d39c] Merge branch 'for-next' of https://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k.git
git bisect bad 42b0664d6f7b3d04f961e0709811280e52d4d39c
# good: [63775c4b77cf7ac5863ae0e76f8626b80d217562] Merge branch 'mm-nonmm-unstable' of https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
git bisect good 63775c4b77cf7ac5863ae0e76f8626b80d217562
# good: [f437936af5c74fddfdfcd2388a5f1eec2f9a105b] Merge branch 'for-next' of https://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap.git
git bisect good f437936af5c74fddfdfcd2388a5f1eec2f9a105b
# good: [01bf3f256f1ed15fa3884e4893e5a9d78fdfb2d6] Merge branch 'for-next' of https://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip.git
git bisect good 01bf3f256f1ed15fa3884e4893e5a9d78fdfb2d6
# bad: [bee649097c8de82d9dccd3660c41163a6507e3d4] Merge branch 'next' of https://git.kernel.org/pub/scm/linux/kernel/git/jenswi/linux-tee.git
git bisect bad bee649097c8de82d9dccd3660c41163a6507e3d4
# bad: [82ccfdd8dd1e29229a3ed7c95a76578706fc4a1d] Merge branch 'for-next' of https://github.com/sophgo/linux.git
git bisect bad 82ccfdd8dd1e29229a3ed7c95a76578706fc4a1d
# good: [32bc5496b48174dbca1f187f710955ee4d9527a1] firmware: arm_scmi: Validate SENSOR_UPDATE payload size
git bisect good 32bc5496b48174dbca1f187f710955ee4d9527a1
# bad: [64251369d33884b431a52b89c60fabf466f3913c] Merge branches 'for-next/scmi/updates' and 'for-next/ffa/updates' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into for-linux-next
git bisect bad 64251369d33884b431a52b89c60fabf466f3913c
# bad: [70492cfce2a4d41e87bf46989028a90f4bc6b38f] firmware: smccc: Fix Arm SMCCC SOC_ID name call
git bisect bad 70492cfce2a4d41e87bf46989028a90f4bc6b38f
# bad: [7fe2ec9fb8e9a78dad8d6b1e551cb4d126e36f1e] firmware: arm_ffa: Set the core device as FF-A device parent
git bisect bad 7fe2ec9fb8e9a78dad8d6b1e551cb4d126e36f1e
# bad: [e659fc8e537c7a21d5d693d6f30d8852f2fa8d91] firmware: arm_ffa: Register core as a platform driver
git bisect bad e659fc8e537c7a21d5d693d6f30d8852f2fa8d91
# good: [cc7e8f21b9f0c229d68cf19a837cba82b5ac2d87] Revert "firmware: arm_ffa: Change initcall level of ffa_init() to rootfs_initcall"
git bisect good cc7e8f21b9f0c229d68cf19a837cba82b5ac2d87
# first bad commit: [e659fc8e537c7a21d5d693d6f30d8852f2fa8d91] firmware: arm_ffa: Register core as a platform driver